Here's some off the wall input that you can only get on a msg board as fucked up and diverese as VV...
S&M is based on the premise that a person is either submissive or dominant. Sure, there are people that can and do enjoy both roles (those people are called "switches") but generally a person is most comfortable in a specific role. After being both exposed and involved in the scene, I cannot help but agree with the philosophy. When you go to an S&M gathering, you can easily identify the subs and doms based on what they wear. However, when I meet these same people in a normal setting, it is still easy to see who would be playing what role even without the visual clues.
Of course, I cannot help but carry this viewpoint into my everyday life. The perfect balance would be 2 switches in a relationship, but I can guarantee you that true switches are rare. Perhaps 1 out of every 100 people in the scene. The chances of that sort of balance happening is extremely rare. Occassionally you get 2 doms that are married and they have a sub they both play with (these are called Pollys), and even more rare would be 2 subs in a relationship. Anyway, like I said, almost everyone is dom/sub, just like your everyday vanilla couples.
Take a momment and think about the various relationships in your circle of friends. There will most likely be a pattern.
I worked this into my dating life and would react to a woman based on what role I precieved them to be. If she seemed submissive, I would play the dominate role a bit more (asking the questions, decinding where to eat and what movie to watch, ect). However, if she seemed rather aggressive, I would become more passive and allow her room to steer the flow of the date, since I assumed that would make her more comfortable. It works for me. Don't get me wrong, I'm not going into dates with a scientific formula or anything like that. These are just the details/subtlties that I think make dating more successful. You certianly cannot judge a person by first looks. However, it only takes a brief interaction before you can pretty much figure out where most would tend to fall, and work the date into your favor. Some people are tricky though. For instance, someone could have an extremely important job directing people, shouting orders, and cracking skulls in thier day to day life. But when they get home and the lights go out, they just want to take a break from all that and have someone else "take charge". Likewise, someone could seem very passive, but become the stereotypical leather clad once they are given the opportunity to cut loose!
Now, I could actually discuss at length the actual degredation of an individual before sex, both the process/technique itself and the psychological implications/impact of the desire or need for an individual to have that
simulated abuse. But seriously, I don't want to derail this thread too much. Besides, tomes have been written to try and explain things of this nature in far greater and better detail than I could ever hope to express on a msg board. Suffice it to say, us humans are strange, complex creatures that do some truely fucked up things!